Multistage centrifugal pump



July 28, 1931. Q HAENTJENS 1,816,775

MULTISTAGE CENTRIFUGLAL PUMP Filed Jan. 17, 1929 ll 21 I 52 I 4 1 P I 1 i w i I o o I M 47 49 53 i r 4 i. .2... W 44 T a INLET INVENTOR OTTO HAENTJENS Patented Jul 28, 1931 OTTO HAENTJENS, OF HAZLETON, PENNSYLVANIA MULTISTAGE GENTRIFUGAL PUMP Application filed January 17, 1929. Serial No. 338,179.

. This invention relates to multi-stage cen trifugal pumps which are rovided' with means for primin the centri ugals, and the main object of this invention is to provide means whereby the connection to the priming pump may be cut off with certainty when the centrifugal has been primed.

In the accompanying drawings:

Fig. 1 is a somewhat diagrammatic illusm tration of a pumping system in which my invention is embodied;

Fig. 2 is a sectional view drawn to a larger scale illustrating a part of the multi-stage centrifugal ump and the priming check valve provi ed with my present invention. For purposes of illustration I have shown in Fig. 1 a general layout of a centrifugal pumpmg system which embodies the principal features of the system of my Patent 1,513,705, dated October 28,- 1924. The centrifugal is shown as a three stage pump at n 5, 5 and 5 to be driven by a motor 18, the

' suction being indicated at 16 and the discharge at 17. I have shown at 19 the priming pump connected by piping 21 and, 22

- through a primin check valve 6 to the first stage of the centrlfugal. There is in addition in this piping connection a vacuur' breaker24 such as disclosed in my above mentioned patent, and there is also a drainage pipe 62 with a drainage check valveat 63 also such as disclosed in the mentioned atent.

The detailed construction of the priming check valve may be in part substantially the same as that disclosed and claimed in my Patent 1,481,199 dated January 15, 1924.

/ The movable part of this priming check valve 10 in the casing 6 is mounted on a' stem 40 13 which finds its bearings in the opposite ends of the casing of the valve. This valve has lateral openings 12 into thevalve chamber and when moved fully to the left finds a seat at 24 toiclose off the connection to the priming pump through the passage Sand pipe'22. The other side of the valve-10 is in l communication through the passage 7 .with l the first stage of'the centrifugal. I

This valve 10 is normally held open, to the right, by a spring or electro magnetic means.

In the drawing I have indicated a solenoid 28 and solenoid core which latter is carried by the stem of the valve as described in my Patent 1,481,199. The operation of the valve thus far will be sufficiently obvious and is fully described in my mentioned patent.

When such a priming check valve is employed in connection with a multi-stage centrifugal pump it has been found that sometimes there is not sufficient pressure in the first stage of the centrifugal to close this priming check valve 10 when the centrifugal has been primed. My present improvement consists in providing means whereby the priming valve shall be closed with certainty at the desired time. For this purpose I extend the stem of the valve 10 to the right and mount thereon a piston 40 working in a chamber 41 closed by a cap 43. Then I provide a communication 44 between the second stage of the centrifugal and the space in the chamber 41 on theright hand side of this piston 40. With this construction I find that the pressure from the second stage on this piston when the centrifugal has been primed and, ,tarted will be suflicient to insure the closing of the valve 10 to its seat 24 an thus shut off the connection with the priming pump at the desired time.

I'claim as my invention:

1. A series multi-stage centrifugal pump in combination with a priming pump connected to the discharge side of the first stage of said centrifugal pump, a primin check valve between the two pumps and en jected to the discharge pressure of said first stage in a direction to close said check valve and means controlled by one of the centrifugal stages other than the first to aid in closin said riming check valve when the centri ugal has been primed and started.

2. A series multi-stage centrifugal pump in combination with a primin pump connected to the discharge side oft e first stagev of said centrifugal pump, a primin check valve in said 'connectlon and subjecte to the discharge pressure of said first stage in a direction to close said check valve, a piston operatively connected to said priming check valve and a connection whereby the pressure 1.00

'. in the second stage of the centrifugal pump may act upon sa1d piston in a direction to close the primmg check' val-ve when the c'en trifugal has been primed and. started. In testimony whereof I have signed my- 1 name to this specification.

"(H-TO- HAENTJTENS} 

